On the suggestion of someone here I tried Phenibut for sleep earlier this year. What I've found with it is that it works best taking it 4-5 days a week with 2-3 days off, otherwise my tolerance builds up. The first day I take it after a break is noticibly stronger and I could probably use a lower dose then (but I ended up just using 900mg all the time). I now do the same with Baclofen 20mg, which I prefer (but Phenibut is more effective for anxiety I hear since it is a weak baclofen plus a weak gabapentin). Anyway, if you want to try lower doeses and haven't tried this already and can go without for a couple of days a week that might work (you might need a longer break at first to clear it out).
Phenibut (and almost certainly Baclofen too) have some interactions with other medications; I had issues with diphenhydramine (numbness in mouth for 10 seconds or so after waking up; I didn't intend to take both, it didn't even seem like a good idea) and L-Theanine (mild asthma reaction, which I otherwise rarely get these days other than in the vicinity of certain cats). While not severe for me, they are the kind of things that could be severe and I think it is worth being careful with them. Withdrawal effects should be less severe with once a day usage due to the short half life (about 6 hours IIRC), but take it long enough without breaks, particularly at high dosage, and it can build up enough to cause withdrawal effects (but tapering when stopping will prevent those).
While I don't remember the details, I tried a benzo for sleep briefly after high school and found it effective only for a day or two. Between that and the potential side effects, I haven't tried them again since. I have a non-24 hour circadian rhythm and have had success with a combination of uridine monophosphate (150mg sublingual daily with maybe monthly breaks of a couple of days), Baclofen (20mg four or five days a week, at least two in a row off), and a quarter of a 5mg melatonin patch most days (I manage to forget it often enough to not need intentional breaks; at least monthly breaks of a couple of days would be a good idea). With this I've been able to avoid my sleep schedule shifting every day as it does without medication. My alertness and other issues during the day still vary quite a bit and are rarely all that good, but hopefully this will get better eventually.
Uridine monophosphate (or triacetyluridine, which is better absorbed from the digestive system but isn't usable sublingually) is also a higher risk in that it hasn't been as comprehensively studied as other things and it could have negative long term effects. I seem to need to take a high B vitamin supplement when I take it or get B vitamin deficiency symptoms (bright red around lips); even a 100% DV supplement doesn't prevent that. The combination of uridine, DHA, and choline is supposed to help with neural growth. I don't know if it would help with anxiety, but anything that helps with sleep seems like a possibility at least :/. It could potentially interact (negatively or otherwise) with things like autoimmune conditions.